Avalara - Cut tax compliance costs, not corners. Avalara automates tax compliance and can help improve accuracy while reducing costs.
KeywordTool.io - KeywordTool.io is the best FREE alternative to Google Keyword Planner and Ubersuggest. It uses Google's autocomplete feature to get over 750+ long-tail keywords for any given query.
TaxJar - TaxJar simplifies sales tax filing for eCommerce sellers.
Google Trends - Explore Google trending search topics with Google Trends.
Thomson Reuters ONESOURCE - ONESOURCE tax software and solutions synchronize every aspect of your work and link international, country, state and local tax laws.
Keywords Everywhere - Free browser add-on for keyword volume, CPC & competition